scholarly journals Semi-synthesis and insecticidal activity of spinetoram J and its D-forosamine replacement analogues

2018 ◽  
Vol 14 ◽  
pp. 2321-2330 ◽  
Author(s):  
Kai Zhang ◽  
Jiarong Li ◽  
Honglin Liu ◽  
Haiyou Wang ◽  
Lamusi A

Spinetoram, a mixture of spinetoram J (XDE-175-J, major component) and spinetoram L (XDE-175-L), is a new kind of fermentation-derived insecticide with a broad range of action against many insect pests, especially Cydia pomonella, Leaf miner and Thrips. Similar to spinosad, spinetoram is friendly to the environment, and non-toxic to animals and human beings. Therefore, spinetoram has been widely applied in pest control and grain storage. In a previous study, we had reported a semi-synthesis of spinetoram J. However, in that synthesis, there were more experimental steps, and the operations were troublesome. So an improved synthesis based on a self-protection strategy was designed and discussed. In this work, 3-O-ethyl-2,4-di-O-methylrhamnose was used as both the reaction substrate of C9–OH and the protecting group of C17–OH. The number of synthetic steps and costs were significantly reduced. In addition, a variety of D-forosamine replacement analogues of spinetoram J were synthesized based on the improved semi-synthesis, and their insecticidal activities were evaluated against third-instar larvae of Plutella xylostella. Although none of the analogues were as potent as spinetoram, a few of the analogues have only a 20–40 times lower activity than spinetoram. In particular, one of these analogues was approximately as active as spinosad. This study highlights the possibility of developing new insecticidal chemistries by replacing sugars on natural products with other groups, and the improved semi-synthesis will be helpful for further researches on spinetoram.

2021 ◽  
Author(s):  
Kunkun Wang ◽  
Benjie Li ◽  
Ye Yu ◽  
Jiaqi Wei ◽  
Jian Zhu ◽  
...  

ABSTRACTBACKGROUNDThe application of RNAi to control pests has attracted the attention of researchers. Our results indicated that knockout of PxRdl2 can decrease resistance to fipronil in Plutella xylostella, providing a suitable target gene for RNAi-based pest control.RESULTSThe differences in the sensitivity of two established homozygous knockout strains of P. xylostella. (Rdl1KO and Rdl2KO) and susceptible P. xylostella to a series of compounds were evaluated. Quinazolines and isoxazolines both showed stronger efficacy in the Rdl2KO strain. Therefore, we proposed a method based on the knockdown of the P. xylostella Rdl2 gene as a tactic to enhance the toxicity of quinazolines and isoxazolines. To reduce costs and protect dsRNA against degradation, we applied a bacterial expression system using the L4440 vector to express PxRdl2 dsRNA in HT115 Escherichia coli. Transformed bacteria (dsRNA-Bac) fed through leaves combined with quinazoline and isoxazolines proved to be more effective in both the susceptible and fipronil-resistant P. xylostella.CONCLUSIONOur results provide a strategy for the development of novel insecticide spray formulations containing dsRNA-Bac, which synergize with insecticide toxins by suppressing PxRdl2, reducing the use of pesticides in the field.


Agronomy ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 57
Author(s):  
Nesrine Chrigui ◽  
Duygu Sari ◽  
Hatice Sari ◽  
Tuba Eker ◽  
Mehmet Fatih Cengiz ◽  
...  

The chickpea leafminer, Liriomyza cicerina (Rondani), is one of the most destructive insect pests of cultivated chickpea (Cicer arietinum L.) in the Mediterranean region under field conditions. For sustainable and environmentally friendly chickpea production, efforts have been devoted to managing the leafminer via decreasing the use of insecticides. Breeding of new resistant varieties is not only an efficient and practical approach, but also cost-effective and environmentally sensitive. To improve resistant varieties, breeders need reliable biochemical selection criteria that can be used in breeding programs. The first objective was to investigate the possible introgression of resistance to the leafminer from C. reticulatum Ladiz. (resistant) to C. arietinum (susceptible), then, to estimate inheritance of resistance to the leafminer for efficient breeding strategies, and finally, to study organic acid contents as selection criteria. Recombinant inbred lines (RILs) and their parents were evaluated using a visual scale of 1–9 (1 = free from leafminer damage and 9 = mines in more than 91% of the leaflets and defoliation greater than 31%) in the field under natural infestation conditions after the susceptible parent and check had scores of >7 on the visual scale. Superior RILs were found for resistance to the leafminer, and agro-morphological traits indicating that introgression of resistance to leaf miner from C. reticulatum to C. arietinum could be possible using interspecific crosses. The inheritance pattern of resistance to the leafminer in RILs was shown to be quantitative. Organic acids, including oxalic, malic, quinic, tartaric, citric and succinic acids in RILs grown in the field under insect epidemic conditions and in the greenhouse under non-infested conditions were detected by using high performance liquid chromatography (HPLC). In general, organic acids were found to be higher in resistant RILs than susceptible RILs. Path and correlation coefficients showed that succinic acid exhibited the highest direct effects on resistance to the leafminer. Multivariate analyses, including path, correlation and factor analyses suggested that a high level of succinic acid could be used as a potential biochemical selection criterion for resistance to leafminer in chickpea. Resistant RILs with a high seed yield resembling kabuli chickpea can be grown directly in the target environments under leaf miner infestation conditions.


2021 ◽  
Vol 70 ◽  
pp. 158-166
Author(s):  
Qiang Zhang ◽  
Wei Dou ◽  
Clauvis Nji Tizi Taning ◽  
Guy Smagghe ◽  
Jin-Jun Wang

2014 ◽  
Vol 30 (10) ◽  
pp. 2655-2662 ◽  
Author(s):  
Zhizhen Pan ◽  
Lian Xu ◽  
Yujing Zhu ◽  
Huai Shi ◽  
Zheng Chen ◽  
...  

2020 ◽  
pp. 115-128
Author(s):  
Aneni T. I. ◽  
Adaigbe V. C. ◽  
Ogbebor C. O. ◽  
Okere C. I. ◽  
Aghayedo C. O.

The leaf miner (Coelaenomenodera elaeidis) is a major pest of the oil palm. It breaks out in epidemic proportions periodically, resulting in severe leaf defoliation and consequently low fresh fruit bunch (FFA) yield. This study analyses temperature, rainfall, relative humidity, and leaf miner abundance records sampled in oil palm fields between 1976 and 1980 in the main station of the Nigerian Institute for Oil Palm Research (NIFOR). Data for temperature, rainfall, and relative humidity were obtained from NIFOR meteorological station. Mathematical relationships between the insect stages (larva, pupa, and adult) and weather factors (rainfall and temperature) were developed indicating that pest predictions can be made for different leaf miner stages using their corresponding model equations giving specific values for rainfall and temperature. Variations in the seasonal patterns of temperature and rainfall are of major significance as a cue to timing leaf miner abundance and would help in making better decisions regarding where farmer action can target pest control interventions, thereby contributing to ensure food security. The need for continuous monitoring has great potential for detection and control of insect pests in oil palm growing areas.


2016 ◽  
Vol 1 (1) ◽  
pp. 41
Author(s):  
. Nurindah

<p>Penerapan teknologi ramah lingkungan budi daya tanaman pada suatu lahan akan dapat mempertahankan kelestarian lingkungan. Penciptaan teknologi budi daya tanaman tembakau, serat, dan minyak industri di-arahkan pada teknologi yang dapat meningkatkan produktivitas dan mutu hasil, efisiensi biaya usaha tani, dan ramah lingkungan. Teknologi ramah lingkungan difokuskan pada penemuan komponen teknologi prapa-nen yang mempunyai dampak minimal terhadap pencemaran atau perusakan lingkungan, yang meliputi va-rietas-varietas unggul, teknik pengendalian hama dan penyakit, teknik konservasi lahan tembakau. Varietas-varietas unggul tersebut adalah varietas-varietas yang mempunyai ketahanan terhadap hama dan penyakit, yaitu tembakau Prancak 95, Prancak N1, Prancak N2, Kemloko 2, dan Grompol Jatim 1; kapas: Kanesia 11–Kanesia 13; kenaf: Karangploso 14–Karangploso 15; wijen: Sumberrejo 4; dan jarak kepyar: Asembagus 81. Teknik pengendalian hama dan penyakit yang ramah lingkungan adalah teknologi pengendalian hama yang membatasi atau meniadakan penggunaan insektisida kimia sintetik dan menerapkan teknik pengendalian de-ngan memanfaatkan peran musuh alami serangga hama atau antagonis patogen penyebab penyakit, dan penggunaan pestisida nabati. Teknik konservasi lahan untuk mengendalikan erosi dan penyakit lincat dikem-bangkan pada lahan tembakau temanggung dengan menerapkan penggunaan varietas tahan penyakit, pem-buatan terassering dan penguatnya, pengolahan lahan minimal, dan aplikasi mikroba antagonis. Teknologi ramah lingkungan tersebut telah diterapkan di tingkat petani dan memberikan dampak yang positif terhadap pengembangan komoditas.</p><p>Technology innovations for tobacco, fibers, and industrial-oil crops are directed to increase production and quality of the products, efficiency, and environmentally-friendly technologies. The efficiency and environ-menttally-friendly technologies are focused on the pre-harvest technology innovations that have minimal im-pacts on environmental damages. The technologies include superior varieties, pest control, and land conser-vation. The superior varieties are those that resistant to either insect pests or diseases, i.e. tobacco: Prancak 95, Prancak N1, Prancak N2, Kemloko 2, and Grompol Jatim 1; cotton: Kanesia 11–Kanesia 13; kenaf: Ka-rangploso 14–Karangploso 15; sesame: Sumberrejo 4; and  castor: Asembagus 81.  Environmentally-friendly pest control is to limit or no use synthetic-chemical pesticides in pest control, but optimally make use the role of natural enemies and antagonists and use biopesticides. Land conservation technique to control erosi-on as well as ”lincat’ disease has been developed in fields of temanggung tobacco by using tobacco variety resistant to the disease, terracering, minimum tillage, and application of antagonist microbes. Those techno-logies has been implemented in the farmers’ fields and has a positive impacts for the commodity develop-ment.</p><p> </p>


1996 ◽  
Vol 14 (1) ◽  
pp. 22-26 ◽  
Author(s):  
D. Casey Sclar ◽  
Whitney S. Cranshaw

Abstract Use of systemic insecticides that can be injected either into the root system or trunk of woody plants provides several potential advantages, notably in control of drift during application. Recently, new classes of insecticides with systemic activity have been developed, which may supplant the organophosphate and carbamate systemic insecticides that have previously been available. To evaluate their potential to control insects affecting shade trees, studies were conducted using imidacloprid and abamectin on elm. Soil injections of imidacloprid appeared particularly effective, controlling all three of the target pest species in this study (elm leaf beetle, European elm scale, elm leaf aphid). Both imidacloprid and abamectin also were effective against at least some elm insects when injected into trunks. Persistence of irnidacloprid was unusually long, providing second season control of all elm insect pests, although root uptake following soil injections was slow.


2020 ◽  
Vol 23 (2) ◽  
pp. 1-6
Author(s):  
Helben Ismat Mohammaed ◽  
Mohammed Saeed Mirza ◽  
Feyroz Ramadan Hassan

Beauveria bassiana is an important entomopathogenic fungus that used as a biocontrol agent of insect pests. Maintaining and preserving B. bassiana cultures is essential for the effective evaluation of its potential as microbial agent against insect pest, for biodiversity studies and also for exchange of fungal material between laboratories. In the present work we evaluated the suitability of four preservation materials based on gelatin and rice to maintain the viability of B. bassiana to be used as baits for insect’s control. The gelatin amended with sugar recorded the maximum viability after 70 days of storage as 98.3% compared to 63.3% on rice media. Effective control of 80% of the ants was observed after 10 days of feeding on gelatin amended with sugar and rice bait. The results demonstrated that treatment with formulations containing conidia of B. bassiana presents insecticidal activity against ant in addition of acting as preservation materials.


Author(s):  
Hong Zeng ◽  
Xiulin Chen ◽  
Yongmin Chen ◽  
Xuejun Pan ◽  
Shunbiao Zhang ◽  
...  

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